The NAS synchronized eg the internal database, even after days only incompletely. Device is fast, but by DLNA-compatible device is not possible to access the most content. As a pure network storage is the box OK, but you can also cheaper. The transfer rates of NAS to NAS or continuous Gigbit LAN are rather average with 40-45MB / s, despite faster SATA-II HDDs.
The slightly more expensive Asus M-25 works better here with similar hardware by far. I've now got a Synology DS212 + yet, almost as a third fallback. This is of course a completely different price class, but after all, comes with sophisticated software. In the long term this will probably be the network non-volatile memory source.
Too bad, but for the NSA-320's then only max. 3 stars.